What to do when Additional FOH (Fuel Operated Heater) doesn't respond when you select the "Turn Additional Heater On" in the VDD Mobile App?

  • On the Service page in the VDD App, check all DTCs (Diagnostic Trouble Codes) related to additional heater. If any occur, fix the heater and clear the DTCs.

  • Other known causes could also be SRS (e.g., crash related), low fuel, low battery or cooling system-related problems

  • If the problem still persists, then your Volvo needs to be configured via VDASH. You'll need to decode the CEM PIN to configure your vehicle's heaters.

For further information on how to decode the CEM PIN of your Volvo, please follow our article.

  • In VDASH, check the settings of Additional FOH – "Clima and Heating > Fuel Heater > With Timer and Additional Heater" must be checked

  • Parking Regime Time should be set to "PAL"

  • In VDASH, check the settings of Additional FOH – "Clima and Heating > Fuel Heater > Additional Heater with Timer" must be checked

  • In VDASH, check the settings of Additional FOH – "Clima and Heating > Heater Type > Fuel Operated Heater, with Timer" must be checked


Alternatively, you could find your nearest PRO / PRO Verified dealer.
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